diff options
Diffstat (limited to 'arch/x86/kernel/reboot_32.c')
-rw-r--r-- | arch/x86/kernel/reboot_32.c | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/arch/x86/kernel/reboot_32.c b/arch/x86/kernel/reboot_32.c new file mode 100644 index 000000000000..0d796248866c --- /dev/null +++ b/arch/x86/kernel/reboot_32.c | |||
@@ -0,0 +1,413 @@ | |||
1 | /* | ||
2 | * linux/arch/i386/kernel/reboot.c | ||
3 | */ | ||
4 | |||
5 | #include <linux/mm.h> | ||
6 | #include <linux/module.h> | ||
7 | #include <linux/delay.h> | ||
8 | #include <linux/init.h> | ||
9 | #include <linux/interrupt.h> | ||
10 | #include <linux/mc146818rtc.h> | ||
11 | #include <linux/efi.h> | ||
12 | #include <linux/dmi.h> | ||
13 | #include <linux/ctype.h> | ||
14 | #include <linux/pm.h> | ||
15 | #include <linux/reboot.h> | ||
16 | #include <asm/uaccess.h> | ||
17 | #include <asm/apic.h> | ||
18 | #include <asm/desc.h> | ||
19 | #include "mach_reboot.h" | ||
20 | #include <asm/reboot_fixups.h> | ||
21 | #include <asm/reboot.h> | ||
22 | |||
23 | /* | ||
24 | * Power off function, if any | ||
25 | */ | ||
26 | void (*pm_power_off)(void); | ||
27 | EXPORT_SYMBOL(pm_power_off); | ||
28 | |||
29 | static int reboot_mode; | ||
30 | static int reboot_thru_bios; | ||
31 | |||
32 | #ifdef CONFIG_SMP | ||
33 | static int reboot_cpu = -1; | ||
34 | #endif | ||
35 | static int __init reboot_setup(char *str) | ||
36 | { | ||
37 | while(1) { | ||
38 | switch (*str) { | ||
39 | case 'w': /* "warm" reboot (no memory testing etc) */ | ||
40 | reboot_mode = 0x1234; | ||
41 | break; | ||
42 | case 'c': /* "cold" reboot (with memory testing etc) */ | ||
43 | reboot_mode = 0x0; | ||
44 | break; | ||
45 | case 'b': /* "bios" reboot by jumping through the BIOS */ | ||
46 | reboot_thru_bios = 1; | ||
47 | break; | ||
48 | case 'h': /* "hard" reboot by toggling RESET and/or crashing the CPU */ | ||
49 | reboot_thru_bios = 0; | ||
50 | break; | ||
51 | #ifdef CONFIG_SMP | ||
52 | case 's': /* "smp" reboot by executing reset on BSP or other CPU*/ | ||
53 | if (isdigit(*(str+1))) { | ||
54 | reboot_cpu = (int) (*(str+1) - '0'); | ||
55 | if (isdigit(*(str+2))) | ||
56 | reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0'); | ||
57 | } | ||
58 | /* we will leave sorting out the final value | ||
59 | when we are ready to reboot, since we might not | ||
60 | have set up boot_cpu_id or smp_num_cpu */ | ||
61 | break; | ||
62 | #endif | ||
63 | } | ||
64 | if((str = strchr(str,',')) != NULL) | ||
65 | str++; | ||
66 | else | ||
67 | break; | ||
68 | } | ||
69 | return 1; | ||
70 | } | ||
71 | |||
72 | __setup("reboot=", reboot_setup); | ||
73 | |||
74 | /* | ||
75 | * Reboot options and system auto-detection code provided by | ||
76 | * Dell Inc. so their systems "just work". :-) | ||
77 | */ | ||
78 | |||
79 | /* | ||
80 | * Some machines require the "reboot=b" commandline option, this quirk makes that automatic. | ||
81 | */ | ||
82 | static int __init set_bios_reboot(struct dmi_system_id *d) | ||
83 | { | ||
84 | if (!reboot_thru_bios) { | ||
85 | reboot_thru_bios = 1; | ||
86 | printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident); | ||
87 | } | ||
88 | return 0; | ||
89 | } | ||
90 | |||
91 | static struct dmi_system_id __initdata reboot_dmi_table[] = { | ||
92 | { /* Handle problems with rebooting on Dell E520's */ | ||
93 | .callback = set_bios_reboot, | ||
94 | .ident = "Dell E520", | ||
95 | .matches = { | ||
96 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), | ||
97 | DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"), | ||
98 | }, | ||
99 | }, | ||
100 | { /* Handle problems with rebooting on Dell 1300's */ | ||
101 | .callback = set_bios_reboot, | ||
102 | .ident = "Dell PowerEdge 1300", | ||
103 | .matches = { | ||
104 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), | ||
105 | DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"), | ||
106 | }, | ||
107 | }, | ||
108 | { /* Handle problems with rebooting on Dell 300's */ | ||
109 | .callback = set_bios_reboot, | ||
110 | .ident = "Dell PowerEdge 300", | ||
111 | .matches = { | ||
112 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), | ||
113 | DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"), | ||
114 | }, | ||
115 | }, | ||
116 | { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/ | ||
117 | .callback = set_bios_reboot, | ||
118 | .ident = "Dell OptiPlex 745", | ||
119 | .matches = { | ||
120 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), | ||
121 | DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), | ||
122 | DMI_MATCH(DMI_BOARD_NAME, "0WF810"), | ||
123 | }, | ||
124 | }, | ||
125 | { /* Handle problems with rebooting on Dell 2400's */ | ||
126 | .callback = set_bios_reboot, | ||
127 | .ident = "Dell PowerEdge 2400", | ||
128 | .matches = { | ||
129 | DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), | ||
130 | DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"), | ||
131 | }, | ||
132 | }, | ||
133 | { /* Handle problems with rebooting on HP laptops */ | ||
134 | .callback = set_bios_reboot, | ||
135 | .ident = "HP Compaq Laptop", | ||
136 | .matches = { | ||
137 | DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), | ||
138 | DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"), | ||
139 | }, | ||
140 | }, | ||
141 | { } | ||
142 | }; | ||
143 | |||
144 | static int __init reboot_init(void) | ||
145 | { | ||
146 | dmi_check_system(reboot_dmi_table); | ||
147 | return 0; | ||
148 | } | ||
149 | |||
150 | core_initcall(reboot_init); | ||
151 | |||
152 | /* The following code and data reboots the machine by switching to real | ||
153 | mode and jumping to the BIOS reset entry point, as if the CPU has | ||
154 | really been reset. The previous version asked the keyboard | ||
155 | controller to pulse the CPU reset line, which is more thorough, but | ||
156 | doesn't work with at least one type of 486 motherboard. It is easy | ||
157 | to stop this code working; hence the copious comments. */ | ||
158 | |||
159 | static unsigned long long | ||
160 | real_mode_gdt_entries [3] = | ||
161 | { | ||
162 | 0x0000000000000000ULL, /* Null descriptor */ | ||
163 | 0x00009a000000ffffULL, /* 16-bit real-mode 64k code at 0x00000000 */ | ||
164 | 0x000092000100ffffULL /* 16-bit real-mode 64k data at 0x00000100 */ | ||
165 | }; | ||
166 | |||
167 | static struct Xgt_desc_struct | ||
168 | real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries }, | ||
169 | real_mode_idt = { 0x3ff, 0 }, | ||
170 | no_idt = { 0, 0 }; | ||
171 | |||
172 | |||
173 | /* This is 16-bit protected mode code to disable paging and the cache, | ||
174 | switch to real mode and jump to the BIOS reset code. | ||
175 | |||
176 | The instruction that switches to real mode by writing to CR0 must be | ||
177 | followed immediately by a far jump instruction, which set CS to a | ||
178 | valid value for real mode, and flushes the prefetch queue to avoid | ||
179 | running instructions that have already been decoded in protected | ||
180 | mode. | ||
181 | |||
182 | Clears all the flags except ET, especially PG (paging), PE | ||
183 | (protected-mode enable) and TS (task switch for coprocessor state | ||
184 | save). Flushes the TLB after paging has been disabled. Sets CD and | ||
185 | NW, to disable the cache on a 486, and invalidates the cache. This | ||
186 | is more like the state of a 486 after reset. I don't know if | ||
187 | something else should be done for other chips. | ||
188 | |||
189 | More could be done here to set up the registers as if a CPU reset had | ||
190 | occurred; hopefully real BIOSs don't assume much. */ | ||
191 | |||
192 | static unsigned char real_mode_switch [] = | ||
193 | { | ||
194 | 0x66, 0x0f, 0x20, 0xc0, /* movl %cr0,%eax */ | ||
195 | 0x66, 0x83, 0xe0, 0x11, /* andl $0x00000011,%eax */ | ||
196 | 0x66, 0x0d, 0x00, 0x00, 0x00, 0x60, /* orl $0x60000000,%eax */ | ||
197 | 0x66, 0x0f, 0x22, 0xc0, /* movl %eax,%cr0 */ | ||
198 | 0x66, 0x0f, 0x22, 0xd8, /* movl %eax,%cr3 */ | ||
199 | 0x66, 0x0f, 0x20, 0xc3, /* movl %cr0,%ebx */ | ||
200 | 0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60, /* andl $0x60000000,%ebx */ | ||
201 | 0x74, 0x02, /* jz f */ | ||
202 | 0x0f, 0x09, /* wbinvd */ | ||
203 | 0x24, 0x10, /* f: andb $0x10,al */ | ||
204 | 0x66, 0x0f, 0x22, 0xc0 /* movl %eax,%cr0 */ | ||
205 | }; | ||
206 | static unsigned char jump_to_bios [] = | ||
207 | { | ||
208 | 0xea, 0x00, 0x00, 0xff, 0xff /* ljmp $0xffff,$0x0000 */ | ||
209 | }; | ||
210 | |||
211 | /* | ||
212 | * Switch to real mode and then execute the code | ||
213 | * specified by the code and length parameters. | ||
214 | * We assume that length will aways be less that 100! | ||
215 | */ | ||
216 | void machine_real_restart(unsigned char *code, int length) | ||
217 | { | ||
218 | local_irq_disable(); | ||
219 | |||
220 | /* Write zero to CMOS register number 0x0f, which the BIOS POST | ||
221 | routine will recognize as telling it to do a proper reboot. (Well | ||
222 | that's what this book in front of me says -- it may only apply to | ||
223 | the Phoenix BIOS though, it's not clear). At the same time, | ||
224 | disable NMIs by setting the top bit in the CMOS address register, | ||
225 | as we're about to do peculiar things to the CPU. I'm not sure if | ||
226 | `outb_p' is needed instead of just `outb'. Use it to be on the | ||
227 | safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) | ||
228 | */ | ||
229 | |||
230 | spin_lock(&rtc_lock); | ||
231 | CMOS_WRITE(0x00, 0x8f); | ||
232 | spin_unlock(&rtc_lock); | ||
233 | |||
234 | /* Remap the kernel at virtual address zero, as well as offset zero | ||
235 | from the kernel segment. This assumes the kernel segment starts at | ||
236 | virtual address PAGE_OFFSET. */ | ||
237 | |||
238 | memcpy (swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS, | ||
239 | sizeof (swapper_pg_dir [0]) * KERNEL_PGD_PTRS); | ||
240 | |||
241 | /* | ||
242 | * Use `swapper_pg_dir' as our page directory. | ||
243 | */ | ||
244 | load_cr3(swapper_pg_dir); | ||
245 | |||
246 | /* Write 0x1234 to absolute memory location 0x472. The BIOS reads | ||
247 | this on booting to tell it to "Bypass memory test (also warm | ||
248 | boot)". This seems like a fairly standard thing that gets set by | ||
249 | REBOOT.COM programs, and the previous reset routine did this | ||
250 | too. */ | ||
251 | |||
252 | *((unsigned short *)0x472) = reboot_mode; | ||
253 | |||
254 | /* For the switch to real mode, copy some code to low memory. It has | ||
255 | to be in the first 64k because it is running in 16-bit mode, and it | ||
256 | has to have the same physical and virtual address, because it turns | ||
257 | off paging. Copy it near the end of the first page, out of the way | ||
258 | of BIOS variables. */ | ||
259 | |||
260 | memcpy ((void *) (0x1000 - sizeof (real_mode_switch) - 100), | ||
261 | real_mode_switch, sizeof (real_mode_switch)); | ||
262 | memcpy ((void *) (0x1000 - 100), code, length); | ||
263 | |||
264 | /* Set up the IDT for real mode. */ | ||
265 | |||
266 | load_idt(&real_mode_idt); | ||
267 | |||
268 | /* Set up a GDT from which we can load segment descriptors for real | ||
269 | mode. The GDT is not used in real mode; it is just needed here to | ||
270 | prepare the descriptors. */ | ||
271 | |||
272 | load_gdt(&real_mode_gdt); | ||
273 | |||
274 | /* Load the data segment registers, and thus the descriptors ready for | ||
275 | real mode. The base address of each segment is 0x100, 16 times the | ||
276 | selector value being loaded here. This is so that the segment | ||
277 | registers don't have to be reloaded after switching to real mode: | ||
278 | the values are consistent for real mode operation already. */ | ||
279 | |||
280 | __asm__ __volatile__ ("movl $0x0010,%%eax\n" | ||
281 | "\tmovl %%eax,%%ds\n" | ||
282 | "\tmovl %%eax,%%es\n" | ||
283 | "\tmovl %%eax,%%fs\n" | ||
284 | "\tmovl %%eax,%%gs\n" | ||
285 | "\tmovl %%eax,%%ss" : : : "eax"); | ||
286 | |||
287 | /* Jump to the 16-bit code that we copied earlier. It disables paging | ||
288 | and the cache, switches to real mode, and jumps to the BIOS reset | ||
289 | entry point. */ | ||
290 | |||
291 | __asm__ __volatile__ ("ljmp $0x0008,%0" | ||
292 | : | ||
293 | : "i" ((void *) (0x1000 - sizeof (real_mode_switch) - 100))); | ||
294 | } | ||
295 | #ifdef CONFIG_APM_MODULE | ||
296 | EXPORT_SYMBOL(machine_real_restart); | ||
297 | #endif | ||
298 | |||
299 | static void native_machine_shutdown(void) | ||
300 | { | ||
301 | #ifdef CONFIG_SMP | ||
302 | int reboot_cpu_id; | ||
303 | |||
304 | /* The boot cpu is always logical cpu 0 */ | ||
305 | reboot_cpu_id = 0; | ||
306 | |||
307 | /* See if there has been given a command line override */ | ||
308 | if ((reboot_cpu != -1) && (reboot_cpu < NR_CPUS) && | ||
309 | cpu_isset(reboot_cpu, cpu_online_map)) { | ||
310 | reboot_cpu_id = reboot_cpu; | ||
311 | } | ||
312 | |||
313 | /* Make certain the cpu I'm rebooting on is online */ | ||
314 | if (!cpu_isset(reboot_cpu_id, cpu_online_map)) { | ||
315 | reboot_cpu_id = smp_processor_id(); | ||
316 | } | ||
317 | |||
318 | /* Make certain I only run on the appropriate processor */ | ||
319 | set_cpus_allowed(current, cpumask_of_cpu(reboot_cpu_id)); | ||
320 | |||
321 | /* O.K. Now that I'm on the appropriate processor, stop | ||
322 | * all of the others, and disable their local APICs. | ||
323 | */ | ||
324 | |||
325 | smp_send_stop(); | ||
326 | #endif /* CONFIG_SMP */ | ||
327 | |||
328 | lapic_shutdown(); | ||
329 | |||
330 | #ifdef CONFIG_X86_IO_APIC | ||
331 | disable_IO_APIC(); | ||
332 | #endif | ||
333 | } | ||
334 | |||
335 | void __attribute__((weak)) mach_reboot_fixups(void) | ||
336 | { | ||
337 | } | ||
338 | |||
339 | static void native_machine_emergency_restart(void) | ||
340 | { | ||
341 | if (!reboot_thru_bios) { | ||
342 | if (efi_enabled) { | ||
343 | efi.reset_system(EFI_RESET_COLD, EFI_SUCCESS, 0, NULL); | ||
344 | load_idt(&no_idt); | ||
345 | __asm__ __volatile__("int3"); | ||
346 | } | ||
347 | /* rebooting needs to touch the page at absolute addr 0 */ | ||
348 | *((unsigned short *)__va(0x472)) = reboot_mode; | ||
349 | for (;;) { | ||
350 | mach_reboot_fixups(); /* for board specific fixups */ | ||
351 | mach_reboot(); | ||
352 | /* That didn't work - force a triple fault.. */ | ||
353 | load_idt(&no_idt); | ||
354 | __asm__ __volatile__("int3"); | ||
355 | } | ||
356 | } | ||
357 | if (efi_enabled) | ||
358 | efi.reset_system(EFI_RESET_WARM, EFI_SUCCESS, 0, NULL); | ||
359 | |||
360 | machine_real_restart(jump_to_bios, sizeof(jump_to_bios)); | ||
361 | } | ||
362 | |||
363 | static void native_machine_restart(char * __unused) | ||
364 | { | ||
365 | machine_shutdown(); | ||
366 | machine_emergency_restart(); | ||
367 | } | ||
368 | |||
369 | static void native_machine_halt(void) | ||
370 | { | ||
371 | } | ||
372 | |||
373 | static void native_machine_power_off(void) | ||
374 | { | ||
375 | if (pm_power_off) { | ||
376 | machine_shutdown(); | ||
377 | pm_power_off(); | ||
378 | } | ||
379 | } | ||
380 | |||
381 | |||
382 | struct machine_ops machine_ops = { | ||
383 | .power_off = native_machine_power_off, | ||
384 | .shutdown = native_machine_shutdown, | ||
385 | .emergency_restart = native_machine_emergency_restart, | ||
386 | .restart = native_machine_restart, | ||
387 | .halt = native_machine_halt, | ||
388 | }; | ||
389 | |||
390 | void machine_power_off(void) | ||
391 | { | ||
392 | machine_ops.power_off(); | ||
393 | } | ||
394 | |||
395 | void machine_shutdown(void) | ||
396 | { | ||
397 | machine_ops.shutdown(); | ||
398 | } | ||
399 | |||
400 | void machine_emergency_restart(void) | ||
401 | { | ||
402 | machine_ops.emergency_restart(); | ||
403 | } | ||
404 | |||
405 | void machine_restart(char *cmd) | ||
406 | { | ||
407 | machine_ops.restart(cmd); | ||
408 | } | ||
409 | |||
410 | void machine_halt(void) | ||
411 | { | ||
412 | machine_ops.halt(); | ||
413 | } | ||